Given the involvement of TDP-43 in ALS/FTLD, Nipped-B in CdLS, and FMRP in the most common form of inherited mental retardation (Fragile X syndrome), these new findings raise the possibility that cognitive deficits and neuronal dysfunction in these conditions may share common molecular mechanisms whether they occur early or late in life. This evidence concerns the gene TARDBP and amyotrophic lateral sclerosis.